Like its predecessors, Resident Evil 4 features lots of unlockables including alternate outfits, post-game scenarios, and secret weapons. There's no single cheat code that unlocks everything in RE4, so you'll have to complete numerous challenges to see everything the PlayStation 2 version has to offer.
The following cheats apply to Evil Resident 4 on PS2; however, many of these cheats also work on the Gamecube, Xbox, and PS4 versions of Resident Evil 4.
May 15, 2007 For Resident Evil 4 on the PC, GameFAQs has 32 cheat codes and secrets.
Complete the main story on any difficulty to access most of the game's bonus content.
After unlocking alternate costumes, you can select your outfit when you start a new game.
You'll get graded on your performance in each level you complete in Mercenaries mode. Getting high marks grants you new characters and weapons to play with in the Mercenaries levels.
Secret weapons can be purchased from the merchant after you start a new game.
Completing challenges in the Separate Ways scenario unlocks Ada's reports, which give you additional information about the characters in RE4.
There are a few things the developers included in the game that serve no practical purpose, but they are fun to see.
This can only be done if Leon is wearing his 'gangster' outfit and has the Chicago Typewriter equipped. Hold R1 to take aim, then press square. This causes Leon to remove his hat, adjust it, then place it back on his head. Continue to do this. On the 4th time, Leon removes the hat, tosses it in the air, catches it, and then strikes a pose.
When you unlock the knight costume for Ashley, not only is she too heavy to be hurt and picked up by Ganados, she'll give Leon some pain. When you need to catch her after jumping down, Leon goes down on a knee and holds his back in pain.
When you climb up a ladder with Ashley, wait until she comes up, then jump back down. You will then need to catch Ashley, but instead of doing that, aim your crosshairs until you see Ashley's skirt. She'll get angry and call you a pervert.
There's a glitch in the castle that prevents the red monk from operating the deadly Gatling gun. After chasing the monk through a series of rooms, you'll end up back in the turret room with the Gatling gun. That's when you can remove the threat:
Immediately leave the torrent room and return to the main hall with the merchant.
Save and quit the game.
Load the game and re-enter the turret room.
When you return to the turret room, the turret is raised, and the red monk is standing outside of the turret ring.
Chase the red monk again.
Shortly after entering the castle, you'll encounter the merchant near a blue door that leads to the shooting range. Look for these doors when you see the merchant to play a target practice mini-game. There are various types of challenges to try, and more are unlocked as you progress through the game. Score as many points as possible to earn bottle caps featuring the characters of RE4.
In the shooting ranges, there is a back wall which looks like the castle and the surrounding area. If you shoot the stars on the back wall, a meteor comes down and destroys the targets that are currently up in the range.